Textile mill spindles



1957 L. J. MOULTON TEXTILE MILL SPINDLES Filed April 2, 1954 I INVENTOR.

A J M004 TON MhHWib (a i United States Patent TEXTILE MILL SPINDLES Lloyd Jackson Moulton, Mentor, Ohio, a'ssignor, by mesne assignments, to Curtiss-Wright Corporation, Marquette Metal Products Division, Cleveland, Ohio, a corporation of Delaware Application April 2, 1954, Serial No. 420,02

9 Claims. (Cl. 57-'130) The drawing shows a known type of textile mill spindle in which a light weight metal (e. g. aluminum) barrel, designed to support a thin-walled tubular bobbin, is strongly anchored at its base portion between a steel shaft and a tubular steel whorl, those three parts being mutually concentric and constituting a rigid spindle blade and whorl unit.

The general object of the invention is to provide an improved composite metal spindle unit of the above iden-' tified type or class, wherein the components can be very strongly secured together in permanent concentric rela tlonship at comparatively low cost in high quantity production. Other objects of the invention will be indicated or explained in the following description of the preferred illustrative forms.

In the drawing, Fig. 1 is mainly a longitudinal central sectional view of one form of spindle blade and whorl unit hereof.

Figs. 2 and 3 are transverse cross sectional views of the construction according to Fig. 1, taken as indicated on that view.

Fig. 4 is an enlarged cross-sectional view, generally similar to Fig. 1, showing a modified form of spindle unit construction. Fig. 4a is fragmentary, partly cross sectional view showmg an upper end portion of the aluminum barrel of the spindle unit according to Fig. 1 or Fig. 4, being treated (by a metal working tool, shown diagrammatically in cross section) to increase the wear resistance of a bobbindriving seat surface on the aluminum barrel.

Fig. 5 is a fragmentary detail sectional view, generally similar to Fig. 4, showing a further modification.

The shaft 1 of spindle unit A, Fig. 1, is assumed to be made of high quality steel, hardened for its full length. Circular portion 3 of the shaft, within the lower cavity of steel whorl 5, is finished for support by a suitable bolster bearing (not shown), and the generally conical lower end portion 4 of the shaft fits the footstep bearing (not shown), in the bolster. Portion 2 of the shaft, upwardly beyond bolster-bearing-engaging surface 3 will, for identification, be referred to as a stub or stub portion of the shaft 1, being anchored in a cylindrical axial bore 6 in the aluminum barrel 10 by interference fitting.

Barrel 10 is preferably made of a light weight metal alloy which is capable of having at least its wear resistance increased by cold working. Forging quality aluminum is one example of such metal. Metal of suitable quality for the barrel is obtainable as bar or tube stock, which latter (not illustrated) would have its bore 6 accurately preformed for reception of the shaft stub 2 by forced fitting, since tube stock can now be obtained with fairly uniform internal diameter and surface finish.

The somewhat reduced diameter or shank portion 8 of the barrel 10 (shown downwardly tapered in 1), is received, as by press or shrink fitting, in a mating bore 9 of whorl 5, mainly in the usual acorn or sleeve portion 11 of the whorl. The acorn extends upwardly beyond the conventionally flanged driving-band-engaging portion 2,802,331 Patented Aug. 13, 1957 12 of the whorl. Upper flange 13 of whorl portion 12 provides an especially strong and rigid anchoring region, axially of the whorl, for the lower end of the shank 8 of aluminum barrel 10.

The upper end peripheral surface portion of the whorl acorn 11, as shown in Figs. 1 and 4, provides a downwardly sloping, i. e. generally conical, bobbin-piloting or circular ramp surface 20 of larger diameter than that of the barrel 10 above said surface 20. Flush surface joint 21 between the aluminum and the steel of the whorl is obtained by cutting away of excess metal of the partly finished whorl and barrel (after assembly of the metal blanks from which those parts will be finish formed as will be described later).

Shank 8 of the barrel 10 may be generally cylindrical (as partially shown at 22 in Fig. 5 in mating interference fitted contact with a generally cylindrical bore 23 of the whorl; in which case a flush surface butt joint such as shown at 24 in Fig. 5 can be provided instead of the type of joint shown in Figs. 1 and 4. Otherwise the construction partially shown in Fig. 5 can, optionally, be according to Fig. l or Fig. 4.

When flexing force is imparted to the upper end of the spindle unit A (e. g. by unbalanced loading or applied during dofling) the region of maximum internal stress is immediately above the bolster bearing. It has been found that, if the components (1, 5 and 10 of the illustrated spindle assembly) are sufficiently strongly maintained against axial relative movement in that region, and the components are enabled to flex more or less independently of each other, especially in portions of the assembly at which fiexure resistance changes somewhat abruptly, and flexure of the spindle is adequately controlled by extension of the steel shaft stub 2 upwardly beyond the whorl, all portions'of the spindle unit will remain concentric with the shaft 1 and in the axial relationship determined by design and assembly. In reference to the shaft 1 and barrel 10 it is found that by permitting independent flexure of the interference fitted parts in the vicinity of the top of the whorl acorn, the effects of fric tional forces tending to cause or allow axial creeping of the shaft out of position are substantially minimized.

An important feature of the present spindle construction, as illustrated in Fig. 1, is that certain of the components are positively interlocked, preferably in the maximum stress region just mentioned above, by permanent deformation of the relatively soft metal of barrel 10 into axially shouldered engagement with one or both of the other components. In Fig. 1, the barrel 10 and the whorl 5 are adequately prevented, as by the coacting shoulders of the above described taper fitting for example, from relative axial movement in one direction; and movement in the opposite direction is positively prevented by upsetting of the metal of the barrel 10 (upset portion at 15), against a shoulder surface 16 of the whorl provided by a suitable radial ofiset in the internal peripheral surface of the whorl. Shoulder 16, as shown, is a chamfer at the lower end of bore 9 of the whorl 5 which suitably locally enlarges the internal diameter of the whorl relative to the lowermost portion of its tapered surface 9. Similarly (and, for example, as part of the same operation as that which locks the barrel and whorl together, e. g'. operation of a tool 17 a portion of which is shown diagrammatically at the right of the spindle unit axis), the metal of the barrel is caused to be permanently seated against an axial shoulder 18 formed on shaft 1. Shoulder 18, as shown, is part of a peripheral groove in the shaft 1, in which case upset portion 19 of the relatively soft metal of the barrel 10 locks the shaft 1 against axial movement relative to the barrel in either possible direction of relative movement of the parts.

The flush surface joint 21 as illustrated in Figs. 1 and 4 between the interface or mating surfaces of whorl and barrel 10, is produced by machining away of excess metal (whorl and barrel blank relationships represented diagrammatically at 5x and x, left Fig. 4) after the blanks are permanently securedtogether as by press fitting. Prior. to such machining ofthe blanks, a center socket or equivalent formation 30 is made in or on the top end of the barrel 10 (or with respect to a bore-closing plug in case aluminum tube stock is employed for the barrel 10), using the bearing surface portions 3 and 4 on the exposed end of the shaft by way of reference as in an appropriate chuck to obtain location for the (e. g.) center socket, so that the removal of excess metal stock from blanks 5x, and 10x will result in a composite structure which is concentric with the shaft 1.

A feature of the construction according to Fig. 1 is that it enables controlled relative gripping ability of two axially widely spaced apart uniform diameter regions (e. g. at 35, and 38) of axial bore 6 of the aluminum barrel in respect to uniform diameter mating bearing portions of shaft stub 2, notwithstanding that the parts are secured together by tight press fitting at uniform temperaures of the parts. Such two basically cylindrical uniform diameter bearing portions of the shaft stub are identified at 35' and 38', Fig. 1, being shown as separated or defined in part by a reduced diameter surface portion 37 of the stub 2 which results in an aluminum-and-steelsurface-separating radial clearance space 6a (purpose explained earlier herein) between the stub and barrel bore 6.

The controlled gripping ability of uniform diameter bore surface regions 35 and 38 in respect to uniform diameter shaft portions 35' and 38' respectively (thus inherently with the same interference fit allowance between both pairs of mating surfaces), is enabled, as shown, by provision of equiangularly spaced relief areas, illustrated as three flats 36 formed on the upper end portion of the shaft stub 2, which flats are coextensive axially with the cylindrical bearing surface portion 35 of the stub. When the steel stub 2 is pressed into the aluminum barrel 10, the metal of the lower bearing region 38 of the bore 6, at locations shown in Fig. 1 as aligned axially with the flats 36, is undisturbed by passage of the stub 2 intothe bore 6. Had bearing portion 35' on the upper end portion of steel stub 2 been a continuous cyl' inder of the same diameter as lower bearing portion 38' then the lower end portion of the bore of the aluminum barrel would have been sufiiciently enlarged in diameter (during the press fitting operation) to prevent the obtaining of an adequately tight gripping of the shaft stub near the bolster bearing. If, in attempting to avoid the difiiculty just above outlined, the lower bearing portion 38 of the shaft had been finished with a slightly larger diameter than that of such above-assumed completely cylindrical upper bearing portion 35 then (particularly since the allowances for forced fitting are highly critical when relatively hard and soft metals are involved) a more serious problem, in the nature of a dilemma, would be presented, namely that of always effecting a reasonably tight interference fit of the upper end portion of the stub in the barrel bore while avoiding an impracticably large interference fitting dimensional relationship of diameters at the lower end portion of the stub. If the steel stub is slightly too large then, during the press fitting, it cuts its way into the aluminum, producing a weak joint.

If, for example, in a construction generally according to Fig. 1, the flats 36 relieve the upper shaft stub hearing portion 35 of half its bore-contacting or bearing area and the lower shaft stub bearing portion 38 is unrelieved (as would be desirable although not so shown), the effective shaft and barrel relative-movement-resisting gripping of the shaft stub by the barrel near the bolster bearing, per unit of axial length of press fitting contact, would be twice that at the upper end portion of the stub.

In the actually illustrated arrangement of Fig; 1 the barrel 10 is made from aluminum bar stock (as against tube stock) and the bore 6 can, economically, be made, as at 612, only slightly longer than the shaft stub portion 2. The flats 36 on upper shaft portion 35, in that case, serve as vents for air and lubricant from the dead end 612 of the bore 6; the annular clearance space 6a serves as a receiving space for such air and lubricant, and/or as a transfer passage therefor in case further venting from the bore 6 is provided for, as by forming (e. g.) flats at 39 on lower shaft stub bearing portion 38' and at circumferential areas which are out of axial alignment with the upper bearing surface portions 35. Flats 39, as shown, are narrow, circumferentially of the shaft, as compared to upper flats 36.

Referring further to flush surface joint 21, Figs. 1 and 4, this is obtained by simultaneously machining away (e. g. by grinding) the excess metal of the whorl and barrel blanks 5x and 10x (left Fig. 4) at an acute angle with reference to the interface or joint-constituting, mating surfaces of the blanks, so that flush, conical surfaces of suitable slope are formed on the aluminum and the steel about the rotational axis of the spindle. The conical surfaces on the aluminum and the steel adjacent the joint line, change slope in such manner as to blend smoothly into adjoining generally cylindrical surfaces of the barrel and whorl, resulting in a circumferential contour whose cross section (as shown, e. g., in Fig. 4) is a reverse curve. Due to simultaneously finishing the two dissimilar metals across the interface, as just described, no exposed rough edges are present on the metal parts. The steel of the whorl around and below the joint line is sloped to provide the circular ramp or bobbin-guiding surface 20 which prevents contact between the bobbin B (ferrule portion of bobbin shown at B, right Fig. 4) and the aluminum of the barrel in proximity to the joint 21. Normally the lower end of the bobbin loosely surrounds the whorl acorn or sleeve portion 11 (that position of bobbin not illustrated).

Fig. 4 also shows a method of effecting a positive mechanical interlock between the spindle unit components, which method requires no tools other than those necessary for press fitting of the components one into another. At the left of the center line, Fig. 4, a portion of shaft 1a is shown with an enlarged diameter or radially offset portion 42, above an annular shoulder 44 of the shaft, which shoulder enables the shaft to be pressed into place in the barrel 10 without likelihood of bending the shaft or damaging its bolster supported surfaces 3 or 4. The bore of the whorl has a complementarily offset or enlarged internal diameter portion which forms a shoulder 45. When the shaft 1a is pressed into place in the bore of the barrel 10 (as shown at the right of the center line in Fig. 4), the lower end portion of the barrel is forced radially outwardly into locking engagement with shoulder 45.

In Fig. 4a the top or tip end portion of the aluminum barrel 10 is shown with a conventional bobbin-engaging tapered (conical) seat surface 45, upwardly beyond which the tip, as shown, has a smooth finishing radius or domelike surface 46. A conveniently driven rotary tool head 47, coaxial with an assumed fixed axial support (not shown) for the finished barrel 10, carries a suitable set (three or more) of hard rollers 50 on rotational axes which, as shown, are coincident with the apex of the conical seat surface 45. A downwardly spring biased plunger 51 on the tool head enters the socket 30 in the spindle tip to guide the rollers. The plunger 51 can be used as a stop (see shoulder 52) to limit or control the movement of the rollers 50, carried by the tool head, axially toward the barrel 10. The action of the hard rollers 50 on the seat surface 45 and radius surface 46 is self evident, being one of cold working the aluminum alloy to increase its wear resistance but without appreciable removal of metal. The metal of the tip, as cold worked by the rollers 50,

will have its surface finish determined by surface characteristics of the rollers. The above described working treatment of the bobbin supporting seat portion of the aluminum spindle results in high residual compressive stress in the metal surface due to controlled plastic flow of the metal.

I claim:

1. A composite, metal, textile mill spindle, comprising a light weight metal barrel adapted to support a bobbin and having an axial bore in its lower end portion, a steel shaft member adapted to be supported for rotation in a bolster on a generally upright axis, the shaft member having a stub portion occupying said bore in interference fitting relationship with said barrel, and a tubular steel whorl member in telescoping interference fitting relationship to the barrel in radial alignment with the stub portions, characterized in that one of said steel members has a radially ofiset peripheral surface portion adjacent the lower end of the barrel, defined, at least in part, by an axial shoulder on said one steel member, and a lower exposed end portion of the barrel is matingly offset so that barrel metal adjacent said end portion is in tight metal-to-metal abutment with said axial shoulder, whereby to lock said one steel member against axial movement downwardly away from the barrel.

2. A composite, metal, textile mill spindle blade and whorl unit comprising a central steel shaft adapted to be supported for rotation in a bolster on a generally upright axis, a light weight metal barrel of circular cross section adapted to support a bobbin and having an axial bore, the defining surface of which is in permanent tight gripping contact with an upper end portion of the shaft, and a steel whorl telescoping the barrel and in interference fitting contact therewith along a lower end peripheral surface portion of the barrel, further characterized in that upset portions of the barrel axially abut annular shoulders on the shaft and whorl, respectively, in a direction positively to lock the barrel against upward movement relative to the whorl and shaft.

3. A composite, metal, textile mill spindle blade and whorl unit comprising a central steel shaft member adapted to be supported for rotation in a bolster, a light weight metal barrel member telescoping an upper end portion of the shaft member and rigidly secured thereto, said barrel member being adapted to support a bobbin, and a steel whorl member for driving the unit, which whorl member and barrel member are in telescoping relationship and have coacting shoulders operating to prevent axial relative movement of those members in one direction, further characterized in that a lower end portion of the barrel member is upset against an axial shoulder of the whorl member whereby to prevent axial relative movement of the whorl and barrel member in the opposite direction.

4. A composite, metal, textile mill spindle blade and whorl unit, comprising a steel shaft having a footstep end portion and a bolster-bearing-engaging circular surface between its ends, a barrel of light weight metal exteriorly formed to support a bobbin, the barrel having an axial bore surface and, along that surface, being tightly secured to a portion of the shaft which lies above its bolster-bearing-engaging surface, and a substantially rigid steel whorl telescoping the barrel and in taper fitted tight contact with a lower end portion of the barrel, the taper fitted surfaces of the barrel and whorl being of decreasing diameter toward the footstep end of the spindle, characterized particularly in that a lower end portion of the barrel is radially outwardly offset, relative to the region of the tapered surface of the barrel nearest thereto, into forced abutment relationship with an axial shoulder on the whorl.

5. A composite, metal, textile mill spindle blade and whorl unit, wherein a light weight metal barrel of circular cross section adapted to support a bobbin is permanently tightly joined to a steel whorl telescoping the barrel at circular mating internal and external peripheral interface surfaces of the whorl and barrel respectively, characterized particularly by provision of a closed joint at the circular interfaces of the barrel and whorl around the upper end of the whorl, the defining exposed surfaces of the joint being flush with each other and conical about the rotational axis of the unit.

6. A composite, metal, textile mill spindle construction comprising a light weight metal barrel adapted to support a bobbin in generally upright position, the barrel having a uniform diameter axial bore of circular cross section intersecting its lower end, a steel shaft adapted to be supported for rotation in a bloster, the shaft having a stub of generally circular cross section integral therewith and occupying the bore and having a generally circular bearing region in interference fitted permanent-jointestablishing relationship to the metal surface defining the bore near the lower end of the bore, an upper end portion of the stub having equiangularly spaced peripheral circular radially rigid bearing regions integral therewith in interference fitting permanent-joint-establishing relationship to the metal surface defining said bore, the spaced bearing regions being defined in part by peripheral surface portions of the stub axially coextensive with the spaced bearing regions and out of contact with the metal surface defining said bore.

7. The spindle construction according to claim 6, wherein the stub has a reduced diameter portion axially separating the first mentioned bearing region from the equiangulary spaced regions and along which portion the metals of the shaft and thebarrel are maintained out of contact with each other during fiexure of the spindle.

8. The spindle construction according to claim 7, wherein the shaft stub, axially coextensively with the first mentioned bearing region, has channel means interrupting its circular surface and co-operating with adjacent surface portions of said bore to provide a. venting channel communicating with the space defined by the reduced diameter portion of the stub and the surface portion of the bore occupied thereby.

9. A composite, metal, textile mill spindle, comprising a light weight metal barrel adapted to support a bobbin and having an axial bore in its lower end portion, a steel shaft member adapted to be supported for rotation in a bolster on a generally upright axis, the shaft member having a stub portion occupying said bore in interference fitting relationship with said barrel, and a tubular steel whorl member in telescoping interference fitting relationship to the barrel in radial alignment with the stub portion, characterized in that said steel shaft member has a pair of axially opposed shoulder surfaces adjacent the lower end of the barrel, and a lower end portion of the barrel is offset toward the axis of the barrel in tight metalto-metal abutment with said axially opposed shoulders, whereby to lock said steel shaft member against axial movement in either direction relative to the barrel.

References Cited in the file of this patent UNITED STATES PATENTS 651,702 Draper June 12, 1900 791,169 Subber May 30, 1905 1,423,378 Wesson July 18, 1922 2,463,484 Gelpke Mar. 1, 1949 2,536,618 Wood Jan. 2, 1951 2,609,254 Harris Sept. 2, 1952 FOREIGN PATENTS 23,432 Great Britain of 1909 522,622 Great Britain June 21, 1940 861,246 France Feb. 4, 1941 

